A conventional rail assembly is widely used on drawers and generally includes a first rail which is fixed to the desk and the second and third rails are connected to the side of the drawer. The second and third rails are retractably connected to each other and both of which are movable in the first rail so that the drawer can be pulled out a desired distance and pushed back completely.
A retrieving unit is used at the end of the first rail which is operatively connected to the second rail so that when the drawer is to be pushed back, the springs of the retrieving unit automatically pulls the drawer inward into the space for the drawer. However, the conventional retrieving unit occupies a certain space and length so that the travel distance of the second and third rails is reduced. In other words, the conventional rail assembly requires longer second and third rails to allow the drawer to be pulled outward to its desired distance which usually three times of the length of the first rail.
As shown in FIG. 9 which shows a conventional rail assembly and includes a first rail (the outer rail not numbered) and a retrieving unit is fixed in an end of the first rail, the retrieving unit includes an extension portion 91. A second rail 90 and a third rail 93 are retractably received in the first rail. The second rail 90 includes a recess 92 defined in an end thereof so that when the second rail 90 is moved toward the retrieving unit, the extension portion 91 is received in the recess 92 and does not interfere the second rail 90. The second rail 90 is then weakened and cannot move to its extreme position because of the springs on two side of the extension portion 91 interfere the second rail 90. The extension portion 91 actually interferes the movement of the third rail 93.
The present invention intends to provide a rail assembly for drawer and the retrieving unit does not interfere the movement of the second and third rails so that both of the second and third rails can be completely retracted in the first rail and can be pulled outward fully.